A second operation, called Aces, targeted illicit betting websites and call centre-type operations in Cambodia, South Korea, the Philippines, Thailand and Vietnam.

More than £10million was seized in the two operations, although Interpol estimates the illegal dens handled nearly £500m in bets during Euro 2016.

"Illegal gambling generates massive profits for organised crime networks which are often linked to corruption, human trafficking and money laundering," said Jim Anderson, the head of Interpol's anti-corruption and financial crimes unit.

The six SOGA operations have resulted in more than 12,500 arrests in total, the seizure of £40m in cash and the closure of more than 3,400 illegal gambling dens which handled almost £4.85billion worth of bets.

But as impressive as these numbers look, one of the world's foremost experts on illegal betting and match-fixing is unconvinced that Interpol's approach is working.

"Interpol has been co-ordinating anti-sport gambling operations in Asia for years now, always with big arrest and seizure figures of the easy-to-detect smaller street operators," said Chris Eaton, a former senior policeman from Australia who has since worked for Interpol, world football's governing body FIFA and the International Centre for Sports Security in Qatar.

"The big organised online gambling operators turning over billions - often infiltrated if not controlled by criminals in safe-haven countries like the Philippines and Malaysia - escape this attention.

"These big international operators under quasi-legal cover are massively vulnerable to fraud and are the source of most of the cash that funds and inspires match-fixing.

"Small-scale and token police operations look good, but tend to enhance the mega illegal operators by cutting out the smaller ones. In this sense it is counter-intuitive.

"Only co-ordinated global government intervention will clean up gambling and save sport, and Interpol would be wiser to encourage this than play with the minor leagues of illegal gambling."